/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: BooleanType.java,v 1.2.4.1 2005/09/05 11:03:37 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler.util;

import com.sun.org.apache.bcel.internal.generic.BranchHandle;
import com.sun.org.apache.bcel.internal.generic.BranchInstruction;
import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.GOTO;
import com.sun.org.apache.bcel.internal.generic.IFEQ;
import com.sun.org.apache.bcel.internal.generic.IFGE;
import com.sun.org.apache.bcel.internal.generic.IFGT;
import com.sun.org.apache.bcel.internal.generic.IFLE;
import com.sun.org.apache.bcel.internal.generic.IFLT;
import com.sun.org.apache.bcel.internal.generic.IF_ICMPGE;
import com.sun.org.apache.bcel.internal.generic.IF_ICMPGT;
import com.sun.org.apache.bcel.internal.generic.IF_ICMPLE;
import com.sun.org.apache.bcel.internal.generic.IF_ICMPLT;
import com.sun.org.apache.bcel.internal.generic.ILOAD;
import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
import com.sun.org.apache.bcel.internal.generic.ISTORE;
import com.sun.org.apache.bcel.internal.generic.Instruction;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.NEW;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.xalan.internal.xsltc.compiler.Constants;

/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 */
public final class BooleanType extends Type {

  protected BooleanType() {
  }

  public String toString() {
    return "boolean";
  }

  public boolean identicalTo(Type other) {
    return this == other;
  }

  public String toSignature() {
    return "Z";
  }

  public boolean isSimple() {
    return true;
  }

  public com.sun.org.apache.bcel.internal.generic.Type toJCType() {
    return com.sun.org.apache.bcel.internal.generic.Type.BOOLEAN;
  }

  /**
   * Translates a real into an object of internal type <code>type</code>. The
   * translation to int is undefined since booleans are always converted to
   * reals in arithmetic expressions.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      Type type) {
    if (type == Type.String) {
      translateTo(classGen, methodGen, (StringType) type);
    } else if (type == Type.Real) {
      translateTo(classGen, methodGen, (RealType) type);
    } else if (type == Type.Reference) {
      translateTo(classGen, methodGen, (ReferenceType) type);
    } else {
      ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
          toString(), type.toString());
      classGen.getParser().reportError(Constants.FATAL, err);
    }
  }

  /**
   * Expects a boolean on the stack and pushes a string. If the value on the
   * stack is zero, then the string 'false' is pushed. Otherwise, the string
   * 'true' is pushed.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      StringType type) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();
    final BranchHandle falsec = il.append(new IFEQ(null));
    il.append(new PUSH(cpg, "true"));
    final BranchHandle truec = il.append(new GOTO(null));
    falsec.setTarget(il.append(new PUSH(cpg, "false")));
    truec.setTarget(il.append(NOP));
  }

  /**
   * Expects a boolean on the stack and pushes a real. The value "true" is
   * converted to 1.0 and the value "false" to 0.0.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      RealType type) {
    methodGen.getInstructionList().append(I2D);
  }

  /**
   * Expects a boolean on the stack and pushes a boxed boolean.
   * Boxed booleans are represented by an instance of
   * <code>java.lang.Boolean</code>.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      ReferenceType type) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();
    il.append(new NEW(cpg.addClass(BOOLEAN_CLASS)));
    il.append(DUP_X1);
    il.append(SWAP);
    il.append(new INVOKESPECIAL(cpg.addMethodref(BOOLEAN_CLASS,
        "<init>",
        "(Z)V")));
  }

  /**
   * Translates an internal boolean into an external (Java) boolean.
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      Class clazz) {
    if (clazz == java.lang.Boolean.TYPE) {
      methodGen.getInstructionList().append(NOP);
    }
    // Is Boolean <: clazz? I.e. clazz in { Boolean, Object }
    else if (clazz.isAssignableFrom(java.lang.Boolean.class)) {
      translateTo(classGen, methodGen, Type.Reference);
    } else {
      ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
          toString(), clazz.getName());
      classGen.getParser().reportError(Constants.FATAL, err);
    }
  }

  /**
   * Translates an external (Java) boolean into internal boolean.
   */
  public void translateFrom(ClassGenerator classGen, MethodGenerator methodGen,
      Class clazz) {
    translateTo(classGen, methodGen, clazz);
  }

  /**
   * Translates an object of this type to its boxed representation.
   */
  public void translateBox(ClassGenerator classGen,
      MethodGenerator methodGen) {
    translateTo(classGen, methodGen, Type.Reference);
  }

  /**
   * Translates an object of this type to its unboxed representation.
   */
  public void translateUnBox(ClassGenerator classGen,
      MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();
    il.append(new CHECKCAST(cpg.addClass(BOOLEAN_CLASS)));
    il.append(new INVOKEVIRTUAL(cpg.addMethodref(BOOLEAN_CLASS,
        BOOLEAN_VALUE,
        BOOLEAN_VALUE_SIG)));
  }

  public Instruction LOAD(int slot) {
    return new ILOAD(slot);
  }

  public Instruction STORE(int slot) {
    return new ISTORE(slot);
  }

  public BranchInstruction GT(boolean tozero) {
    return tozero ? (BranchInstruction) new IFGT(null) :
        (BranchInstruction) new IF_ICMPGT(null);
  }

  public BranchInstruction GE(boolean tozero) {
    return tozero ? (BranchInstruction) new IFGE(null) :
        (BranchInstruction) new IF_ICMPGE(null);
  }

  public BranchInstruction LT(boolean tozero) {
    return tozero ? (BranchInstruction) new IFLT(null) :
        (BranchInstruction) new IF_ICMPLT(null);
  }

  public BranchInstruction LE(boolean tozero) {
    return tozero ? (BranchInstruction) new IFLE(null) :
        (BranchInstruction) new IF_ICMPLE(null);
  }
}
